Bug 433806

Summary:	Windows automatically exit fullscreen
Product:	[Plasma] kwin	Reporter:	Riccardo Robecchi <sephiroth_pk>
Component:	compositing	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED FIXED
Severity:	normal	CC:	kde, nate
Priority:	NOR
Version First Reported In:	5.21.1
Target Milestone:	---
Platform:	Neon
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:

Description Riccardo Robecchi 2021-03-01 18:25:41 UTC

SUMMARY
Windows instructed to work in fullscreen mode, e.g. Skype or Firefox playing YouTube, automatically exit that mode without any prompt from the user and repeatedly do so if the user re-enables fullscreen.

STEPS TO REPRODUCE
1. Play a video on YouTube on Firefox
2. Make it fullscreen

OBSERVED RESULT
After a while, the video exits fullscreen.

EXPECTED RESULT
The video stays in fullscreen mode until the user exits it voluntarily.

SOFTWARE/OS VERSIONS
Linux: KDE Neon
KDE Plasma Version: 5.21.1
KDE Frameworks Version: 5.79.0
Qt Version: 5.15.2

ADDITIONAL INFORMATION
Using Mesa git updated to 23 February 2021 with an AMD Radeon Vega 8 GPU (in a Ryzen 5 2500U).

Comment 1 Nate Graham 2021-03-02 16:24:47 UTC

Never seen this. How strange.

Does it stop happening if compositing is disabled?

Comment 2 Riccardo Robecchi 2021-03-02 16:29:15 UTC

(In reply to Nate Graham from comment #1)
> Never seen this. How strange.
> 
> Does it stop happening if compositing is disabled?

It seems like it does stop. I just tried watching a brief video (https://youtu.be/7IOG92WEkOc): during the first half I disabled compositing and it worked as it should; in the second half I enabled compositing again and after a few seconds it exited fullscreen mode.

Comment 3 Nate Graham 2021-03-02 16:30:35 UTC

Thanks for the info!

Comment 4 David Edmundson 2021-03-02 16:51:06 UTC

X or wayland?
How are you entering the fullscreen?

We need something to indicate that it's kwin at fault

Comment 5 Riccardo Robecchi 2021-03-02 18:21:30 UTC

(In reply to David Edmundson from comment #4)
> X or wayland?
> How are you entering the fullscreen?
> 
> We need something to indicate that it's kwin at fault

X. In the case of YouTube videos I use the bespoke button of the Web player. The same happens with Skype and Teams, in which case I either double-click on the window or select "fullscreen" from the options.
This happens throughout different applications and that it doesn't happen when compositing, so if it isn't KWin directly I suspect it may be how it reacts to something else.

Comment 6 Riccardo Robecchi 2023-03-17 15:22:05 UTC

Closing as I haven't experienced this in a while.